This invention relates generally to the art of computers and more specifically to computer systems involving cursor control devices commonly known as computer mice.
Generally, a computer mouse is a small, box-like, device having an electro-mechanical location generator mounted therein for generating signals indicative of the movement of the mouse on a work surface. These signals are sent to a computer. For example, one presently popular computer mouse includes a hard elastic ball housed within and protruding through the bottom of a mouse housing which rolls across the work surface beneath the mouse housing when the mouse is moved. Electrical circuits within the mouse housing monitor rotations of the elastic ball to generate signals indicative of the changes in location of the mouse and these signals are sent to a computer.
Usually a computer mouse also includes a hand-actuated acceptance switch thereon which can be, and usually is, actuated by a button which is usually located on top of the mouse housing. Usually, the mouse is connected to the computer through a flexible electrical cable. With appropriate software in the computer, the location signals sent thereto by the mouse cause a cursor which shows up on a video display of the computer to move in accordance with movement of the mouse. Thus, the cursor is a video prompt which shows a computer user where he is working within a computer display and which is controlled by movement of the mouse on the work surface. When the computer user desires that the computer accept a particular location of the cursor into its memory to be used by the computer, he actuates the acceptance switch, usually a button on the mouse, with the same hand with which he is moving the mouse about. In a menu driven program, the mouse might be used to locate and select options from a menu. In a graphic program, however, the mouse is usually used to locate elements of a graphic display, such as the three points describing a triangle. When the mouse is used for producing a particular graphic display it is sometimes necessary to precisely place and accept the locations of the cursor. Placing the cursor and accepting particular locations thereof into the computer memory with a mouse is usually easy, but at times, such acceptance can be quite "tricky". This problem normally occurs when one is drawing fine details of a graphic display which require great accuracy. When the cursor is at a desired location it is usually difficult to prevent any movement of the mouse while pressing the acceptance button on the mouse. If the mouse does move while pressing the button, the cursor also moves and the wrong location is accepted by the computer, and this operation must then be deleted and repeated to obtain a desired accuracy. Sometimes it is necessary to repeat this procedure two or three times before an actual, finally-located, position has been accepted by the computer. Such a procedure is time consuming and quite annoying to the computer operator. Thus, it is an object of this invention to provide an accessory for a cursor control device, such as a computer mouse, which avoids any inadvertent movement of the device and cursor resulting from actuation of an acceptance switch on the device.
It is a further object of this invention to provide such an accessory for a computer mouse which is uncomplicated in structure and in use.
It is a further object of this invention to provide such an accessory for a computer mouse which can be added to a computer system in which a mouse and a computer already exist.